Incident tolerant turbine design is a major challenge for any turbomachinery designer. High Pressure turbines experience large aerodynamic losses when operating at reduced massflow and lower RPM. The turbine performance is abated by the positive incidence, at which the flow impacts the rotor airfoils, moving the stagnation point towards the pressure side, causing a separation bubble in the front suction side. In marine life, a diverse range of animals have developed wave surfaces along their fins to prevent flow separation at similar Reynolds numbers for incompressible fluids.

This paper describes a new wave parameterization strategy for optimizing wavy airfoils, to offer superior performance at positive incidence. The objective is to discover the right combination of waves at the airfoil leading edge, trailing edge, characterized by their amplitude, phase, and frequency, such that they offer the lowest possible pressure losses at 15 degrees positive incidence. The optimization is performed on an turbine passage, optimized for best efficiency at nominal conditions, while maintaining the same exit flow angle and massflow. The results of the optimization show a clear benefit at positive incidence, at the expense of a slightly lower performance at nominal conditions. A final comparison of the optimized rotor with stage is included in the analysis.


Bio-Inspired High Pressure Turbine Optimization Strategy for Hybrid-Electric Engines Operating at Off-Design

Division / Sponsor:
International Gas Turbine Institute (IGTI)

Paper Proceedings: https://asmedigitalcollection.asme.org/GT/GT2020/volume/84058

Turbo Expo - Virtual Conference

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.